1. Technical Field
The present disclosure relates to a touch detection device, a display device with a touch detection function, and a cover member.
2. Description of the Related Art
A touch detection device called a touch panel that is capable of detecting an external proximity object has recently been attracting attention. The touch panel is used in a display device with a touch detection function such that the touch panel is mounted on or integrated with a display device such as a liquid crystal display device. The display device with a touch detection function displays, for example, various button images on the display device, using the touch panel in place of normal mechanical buttons to receive an information input.
Japanese Patent Application Laid-open Publication No. 2014-174760 (JP-A-2014-174760) discloses a display device with a touch detection function in which a button through which a zero-dimensional (0D; on and off) input is performed is provided outside of a display region. The display device with a touch detection function disclosed in JP-A-2014-174760 includes a touch detection electrode extending from the display region to the outside of the display region, and a drive electrode that is capacitively coupled with the touch detection electrode outside of the display region. A touch input on the button is detected based on a change in mutual capacitance of the touch detection electrode and the drive electrode outside of the display region.
The display device with a touch detection function disclosed in JP-A-2014-174760 needs to provide the drive electrode that is capacitively coupled with the touch detection electrode outside of the display region, potentially complicating the device.